cloning


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Related to cloning: Human cloning

clon·ing

(klōn'ing),
1. Growing a colony of genetically identical cells or organisms in vitro.
2. Transplantation of a nucleus from a somatic cell to an ovum, which then develops into an embryo; many identical embryos can thus be generated by asexual reproduction.
3. Replication of genetically identical embryos by microsurgical division of a blastocyst and implantation of resulting cells in animal wombs for gestation.
4. "Therapeutic" cloning: growth of somatic stem cells in an embryo that has been produced by fertilization in vitro and modified by replacement of its nuclear material with DNA from a host with deficient or diseased tissue (for example, heart, liver, pancreas). Subsequent harvesting of the stem cells for implantation in the host subject results in destruction of the embryo.
5. A recombinant DNA technique used to produce millions of copies of a DNA fragment. The fragment is spliced into a cloning vehicle (that is, plasmid, bacteriophage, or animal virus). The cloning vehicle penetrates a bacterial cell or yeast (the host), which is then grown in vitro or in an animal host. In some cases, as in the production of genetically engineered drugs, the inserted DNA becomes activated and alters the chemical functioning of the host cell.

cloning

[klō′ning]
a procedure for producing multiple copies of genetically identical organisms or cells or of individual genes. Organisms may be cloned by transplanting blastocysts from one embryo into an empty zona pellucida, or nuclei from the cells of one individual into enucleated oocytes. Cells may be cloned by growing them in culture under conditions that promote cell reproduction. Genes may be cloned by isolating them from the genome of one organism and incorporating them into the genome of an asexually reproducing organism, such as a bacterium or a yeast.
The generation of an exact living replica of an organism’s DNA—DNA cloning—or a cell—cell cloning—produced asexually from a single ancestor
Biotechnology DNA cloning in recombinant technology, DNA manipulation to produce multiple copies of a single gene or DNA segment
Genetics The process of asexually producing a group of genetically identical cells or clones, all from a single ancestor
Molecular biology The production of multiple, genetically identical molecules of DNA, cells, or organisms, which involves reverse transcription of purified mRNA into the corresponding cDNA before insertion into a vector, the synthesis of multiple copies of a DNA sequence, previously introduced into E coli, grown in the bacteria in culture media, removed, and DNA segments of interest isolated

clon·ing

(klōn'ing)
1. Growing a colony of genetically identical cells or organisms in vitro.
2. Transplantation of a nucleus from a somatic cell to an oocyte, which then develops into an embryo; many identical embryos can thus be generated by asexual reproduction.
3. Replication of genetically identical embryos by microsurgical division of a blastocyst and implantation of resulting cells in animal wombs for gestation.
4. Therapeutic cloning: growth of somatic stem cells in an embryo that has been produced by in vitro fertilization and modified by replacement of its nuclear material with DNA from a host with deficient or diseased tissue (e.g., heart, liver, pancreas); subsequent harvesting of the stem cells for implantation in the host subject destroys the embryo.
5. A recombinant DNA technique used to produce millions of copies of a DNA fragment. The fragment is spliced into a cloning vehicle (i.e., plasmid, bacteriophage, or animal virus). The cloning vehicle penetrates a bacterial cell or yeast (the host), which is then grown in vitro or in an animal host. In some cases, as in the production of genetically engineered drugs, the inserted DNA becomes activated and alters the chemical functioning of the host cell.

cloning

specialized technology for the generation of identical copies of DNA molecules or of genetically identical copies of cells or organisms. See CLONE, THERAPEUTIC CLONING, CELL CULTURE, RECOMBINANT DNA TECHNOLOGY, DOLLY the sheep.

cloning

see recombinant DNA technology.

directional cloning
the insertion of a segment of foreign DNA which has a defined polarity, e.g. different restriction enzyme sites at each end, into a plasmid vector.
References in periodicals archive ?
Cloning animals is not new science, with the first animal, a tadpole, being cloned in 1952.
Cloning today is done mostly in South America and Asia, and infrequently in the United States, Hinrichs says.
According to the Commission's impact assessment, cloning technology is being applied to cattle in the US, Canada, Argentina, and Australia.
We know that animal welfare is affected by cloning -there is no scientific doubt on this.
Cloning involves removing the DNA from the nucleus of an egg cell taken from a mother and replacing it with genetic material contained in a cell taken from whatever is being cloned.
Increasingly, "reproductive" cloning is said to occur only if a cloned human being is brought to full term and born alive.
And if that's the case, scientists who wish to create stem cells by cloning might have a new source of support to back them up: the U.
The ``somatic cell nuclear transfer,'' however, is what's called ``therapeutic cloning,'' meaning the sort of cloning in which a lab can make hundreds of thousands of tiny humans and drop them in a blender with no one the wiser and no one caring.
Hwang's research took the first steps in therapeutic cloning, a process in which stem cells (cells that can become any one of the 200 different cell types present in the human body) are taken from a cloned embryo.
What are the social representations of cloning risks and benefits?
What is important is to always assess the data requirements for a particular testing phase to determine whether cloning the database in an operational clustered environment is truly needed.